[PATCH 0/2] wireguard-linux-compat: grsecurity compat patches

[Jason A. Donenfeld]

Hi Mathias,

On Mon, Dec 13, 2021 at 5:32 PM Mathias Krause <minipli at grsecurity.net> wrote:
>
> Am 13.12.21 um 15:37 schrieb Jason A. Donenfeld:
> > On Mon, Dec 13, 2021 at 3:33 PM Mathias Krause <minipli at grsecurity.net> wrote:
> >> yeah, don't worry. We can keep this change downstream in grsec. Dunno if
> >> Jason wants to take it as well, his call. It was just a side observation
> >> which came out of our need to read and understand the code to provide a
> >> workaround for the gcc bug we were hitting.
> >
> > I suppose I can load it up in kbench9000 to see if it makes a
> > difference. If it doesn't matter much, I'd prefer sticking with the
> > formally verified stuff. But if there is a nice speedup, then I guess
> > we can revisit more handwavy "obviously this is the same thing"
> > arguments.
>
> Had to hack main.c and run.sh a little, but here are some numbers:
>
> root at box:~# ./run.sh
> [+] Setting no-turbo to status 1
> [+] Setting non-boot CPUs to status 0
> [+] Inserting module to run tests
> insmod: ERROR: could not insert module kbench9000.ko: Unknown symbol in
> module
> [+] Gathering results
>                  ever64: 115100 cycles per call
>            ever64_out_r: 115080 cycles per call
>           ever64_out_rm: 113957 cycles per call
> [+] Setting non-boot CPUs to status 1
> [+] Setting no-turbo to status 0
>
> Slightly faster.

Huh, that's actually a pretty nice speedup for just changing register
allocation... What CPU is this?

Jason